The invention relates to a padlock, more particularly to a padlock assembly with a two-part U-shaped lock casing.
Referring to FIG. 1, a conventional padlock assembly is shown to include a U-shaped lock casing 10, a key-operated lock mechanism 16 mounted in the lock casing 10 at a lower portion thereof, and a straight shackle bar 14 with first and second shackle grooves 141, 142 and inserted into an upper portion of the lock casing 10 for retaining an object 1 on the lock casing 10.
As illustrated, the lock casing 10 has a lock core mounting portion 101 that defines a lock core receiving space 160 in a longitudinal direction, and first and second shackle mounting portions 11,12 that extend from one side of the lock core mounting portion 101 in a transverse direction. The first and second shackle mounting portions 11, 12 are spaced apart from each other in the longitudinal direction. The first shackle mounting portion 11 has a shackle passage 111 in the longitudinal direction, and a first tumbler retention hole 110 in the transverse direction and in communication with the shackle passage 111. The second shackle mounting portion 12 is formed with a shackle retaining blind hole 121 aligned with the shackle passage 111, and a second tumbler retention hole 151 in the transverse direction and in communication with the blind hole 121 and the core receiving space 160. The lock mechanism 16 includes a cylindrical lock core 161 disposed in the lock core receiving space 160 and rotatable thereinside between locking and unlocking positions upon insertion of a corresponding key, a first spring-loaded tumbler 112 disposed in the first tumbler retention hole 110, and a second spring-loaded tumbler 15 disposed in the second tumbler retention hole 151 and connected operably to one end of the lock core 161 so as to be co-rotatable therewith such that the second spring-loaded tumbler 15 will retract into the second tumbler retention hole 151 when the lock core 161 is at the unlocking position, thereby permitting removal of the shackle bar 14 in the longitudinal direction away from the first shackle mounting portion 11.
Some of the disadvantages of the aforesaid lock apparatus are as follows:
(a) The lock core 161 is not removable from the lock receiving space 160. As such, in case of spring fatigue that can lead to undesired disengagement between the shackle bar 14 and the tumblers 112, 15, the entire padlock assembly has to be discarded.
(b) When an object 1 is inserted between the first and second shackle mounting portions 11, 12 so as to be retained on the shackle bar 14, the engaging hole 2 of the object 1 is generally concealed by the shackle mounting portions 11, 12. As a result, the user has to feel and move, with the assistance of his fingers, the engaging hole 2 of the object 1 into alignment with the shackle passage 111 and the blind hole 121 prior to insertion of the shackle bar 14 between the first and second shackle mounting portions 11, 12. This inconveniences the user of the conventional padlock assembly.
The main object of this invention is to provide a padlock assembly which is clear of the aforesaid disadvantages that generally result from the use of the conventional padlock assembly.
Accordingly, the padlock assembly of the present invention includes a first lock casing part, a key-operated lock mechanism, a second lock casing part, and a shackle bar. The first lock casing part has a hollow lock core mounting portion with front and rear end surfaces that are spaced apart from each other in a longitudinal direction. The lock core mounting portion is formed with a core receiving space that extends in the longitudinal direction through the front and rear end surfaces. A first shackle mounting portion extends in a first transverse direction relative to the longitudinal direction from one side of the lock core mounting portion. The lock mechanism includes a cylindrical lock core formed with a key hole and disposed in the core receiving space. The lock core is adapted to be rotated inside the core receiving space upon insertion of a corresponding key into the key hole. The lock core has one end adjacent to the rear end surface of the lock core mounting portion. A latch member is connected to the one end of the lock core and is disposed outwardly of the core receiving space. The second lock casing part has a latch engaging portion with front and rear ends. The latch engaging portion is formed with a latch recess that extends from the front end toward the rear end, and a latch retainer disposed inside the latch recess to partition the latch recess into a latch entrance portion proximate to the front end of the latch engaging portion, and a latch retention portion proximate to the rear end of the latch engaging portion. The latch member is extendible into the latch retention portion via the latch entrance portion and is rotatable thereinside between locking and unlocking positions. The latch retainer engages the latch member when the latch member is disposed in the latch retention portion to prevent removal of the latch member from the latch retention portion in a direction away from the rear end of the latch engaging portion. A second shackle mounting portion extends in a second transverse direction parallel to the first transverse direction from one side of the latch engaging portion. The shackle bar extends between the first and second shackle mounting portions, and has at least one end connected removably to a respective one of the first and second shackle mounting portions.